jon lapook has the latest. and elaine quijano on a debt america can never fully repay. owed to this hometown hero. >> this is awesome. okay? ( cheers ) yeah. . captioning sponsored by cbs this is the "cbs evening news" with scott pelley. >> pelley: good evening. tonight's face-off between vice than vit joe biden and congressman paul ryan is getting a lot more attention than vice presidential debates usually get. the obama campaign is looking to biden to stop the momentum mitt , mney has enjoyed since the debate in denver, which governor romney was widely perceived to job is . ling.s job is to keep romney's al gallu rolling. today's national gallup poll of likely voters shows governor romney with a slender lead of one point over the president. of course, that's within the lly a tie.error so it's essentially a tie. tonight's debate is at centre college in danville, kentucky. nancy cordes and jan crawford danville. first we'll go to nancy, covering the vice president's campaign. nancy. >> reporter: scott the vice president arrived here in kentucky today after several days